Electrical disconnects are used in a variety of commercial applications, both indoors and outdoors, for energizing and de-energizing electrical devices, such as lights, fans, pumps, generators and the like. Typically, an electrical disconnect includes an external handle connected to a switch element located within an electrical enclosure, or box. The handle may or may not include lockout features to prevent unauthorized operation of the associated electrical device.
As will be appreciated, electrical disconnects and associated electrical enclosures find wide industrial application, and thus they may be employed in a variety of environments. Some environments may be subject to rain (for outdoor applications), water spray (for indoor applications in which a hygienic work space is required) and/or dust. In addition, due to the increasing intensity of weather events, it may become important for electrical devices to withstand temporary or permanent submersion.
The National Electrical Manufacturers Association (NEMA) and Underwriters Laboratories (UL) provides standards for protection provided by certain enclosure “types.” For example, NEMA Type 6/6P enclosures must provide protection from ingress of solid foreign objects, as well as the ingress of hose directed water and water during temporary or prolonged submersion at a limited depth. Similarly, the International Electrotechnical Commission (IEC) also provides standards for protection of enclosures. For example, an enclosure meeting the IEC's International Protection (IP) Code IP67, IP68 or IP69 must provide protection from dust, as well as protection from powerful jets of water and/or total immersion of the enclosure. In addition, NEMA/UL50E type 6, 6p and IEC equivalent IP67, IP68 provide standards for enclosures subjected to temporary submersion (on the order of minutes) and permanent submersion (on the order of hours or days).
Further, the Occupational Safety & Health Administration (OSHA) provides standards for lockout of electrical disconnects using one or more external locks. Such lockout controls can be important when machinery is being serviced to ensure the safety of workers in the area. Under 29 C.F.R. §§1910.269, OSHA provides standards for such “Hazardous energy control (lockout/tagout)” procedures. Finally, in applications such as health care and food service industries, a variety of independent hygiene/sanitary standards (e.g., National Sanitation Foundation (NSF) standards; American National Standards Institute (ANSI), the US Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS), International Association of Milk, Food and Environmental Sanitarians (IAMFES), American Meat Institute (AMI)), as well as harmonized industry standards must be adhered to so that the handles and other external surfaces of electrical disconnects can be thoroughly cleaned on a periodic basis. Similar European standards also exist.
As can be appreciated, problems exist with the existing handle and seal designs for electrical disconnects which may not be capable of simultaneously meeting all of the aforementioned sealing, lockout, and cleanability requirements. Accordingly, it would be desirable to provide an improved load switch handle and seal assembly that includes enhanced locking and sealing features that provide a desired high degree of moisture and water resistance and which is easily cleanable to meet applicable hygiene/sanitary standards.